Unable to view task in MWS : Error Portlet "null" is not found"

Getting below error when viewing Task in my inbox in MWS. No form etc showing.

Please help
[POP.001.0002] A “java.lang.RuntimeException” occurred with the Message “com.webmethods.portal.PortalException: [POP.007.0075] Portlet “null” is not found”